He never takes care of my sister but now knows how I should take care of her when I don't take care of her

I'm 15 for reference.

My sister(6 years old) was coming into my room over and over, refusing to get out, running around, etc repeatedly until I was screaming at her to get out whenever she would come in loud enough to hurt my throat. I knew my dad was there, my dad never really does anything if I'm being honest, he just sits there and observes. This moment was no different.

I was screaming at her to get out at the top of my lungs to the point that I asked my brother to tell her to get out for me because it hurt me to keep screaming.

My dad did nothing, I didn't expect him to, I knew he was there but I was alone on it.

Then, I yell at her to get out again. I was drawing during this. My dad walks towards the door and says, "you need to change the way you speak to her"

I knew he was talking to me but I ignored him, I just kept drawing. Then he said, "I'm talking to you" and I looked up and said, "I know" pretty bluntly.

He said, "I would've helped with her if you didn't keep screaming at her" and I wanted to respond to him with, "and I wouldn't have screamed if you helped with her" but I just didn't say anything. I just looked at him.

Then he went on about how screaming at her will only encourage her to keep going and that we(being me and my brother) need to change our approach when we talk to her.

And all I was thinking was that we're the only ones that do talk to her so it makes no sense for him to tell us how to, since he's basically not even there even when he is.

So that was something